Children have long been fascinated by the appearance of illuminated or brightly-colored objects. Toy manufacturers have recognized this affinity, and currently provide a variety of different toys or novelty articles that are illuminated or brightly-colored.
Another enticing element common to many toys is a hand-holdable configuration. In other words, many children are highly attracted to and enjoy using a hand-holdable toy or novelty article which can be held and carried by the user. In this regard, several toys have been designed, for example, to include an elongated tube or stick, so as to resemble a magic wand or toy sword.
Some toys include a combination of illuminated or brightly-colored objects with a handle. For example, perhaps influenced by the movie xe2x80x9cStar Warsxe2x80x9d(copyright), hand-holdable toys, some of which are sold under the trade designation xe2x80x9cLIGHT SABERxe2x80x9d, are available. Generally, such toys include a colored, semi-transparent tube attached to a handle. The handle may further include a switch for activating an interior light source to illuminate the tube.
Other hand-holdable, illuminated novelty articles have also been devised, including fluorescent-colored cylinders (see, e.g., U.S. Pat. No. 4,678,608 (Dugliss); U.S. Pat. No. 4,717,511 (Koroscil); U.S. Pat. No. 5,043,851 (Kaplan); U.S. Pat. No. 5,122,306 (Van Moer et al.); and U.S. Pat. No. 5,232,635 (Van Moer et al.) and U.S. Design Pat. No. 331,889 (Kaplan)). Such cylinders are commonly comprised of a flexible plastic outer tube and a brittle inner tube. A first liquid is maintained within the inner tube and a second liquid maintained between the outer tube and the inner tube. When the cylinder is bent, the inner tube breaks, allowing the two liquids to mix. The resulting mixture produces a xe2x80x9cglowingxe2x80x9d effect. Such novelty articles are available, for example, from The Coleman Company, Inc. of Kansas under the trade designation xe2x80x9cILLUMISTICKSxe2x80x9d, and from Omniglow Corp. of Portsmouth, N.H. under the trade designation xe2x80x9cSNAPLIGHTxe2x80x9d.
While illuminated tubes and fluorescent-colored cylinders do present articles appealing to children, some inherent limitations may exist. For example, illuminated tubes and fluorescent-colored cylinders are generally unable to produce multiple colors. While it may be possible, for example, to have different colored layers of plastic as part of the illuminated tube, these colors normally will not change during use. It is believed that a multi-colored object is highly attractive. Thus, an important attribute appealing to children is unfulfilled by existing illuminated tube and fluorescent-colored cylinder toys.
Toy and other novelty article manufacturers are continually attempting to produce hand-holdable entertainment devices or toys which function in the dark. Further, many children and adults alike desire to purchase and use such products. Although there are several products available which combine an illuminated object with a handle, a need exists for a hand-holdable toy capable of producing a multi-colored, illuminated effect.
The present invention provides a hand-holdable toy light tube comprising a handle (including a first end), and a tube (including a cylinder or cone) of color shifting film extending from the first end, and a light source (i.e., the article includes a source that generates light as opposed to one that merely reflects ambient light) connected to (including within) the handle, wherein the light source is configured to be activated by a power source. Preferably, the light source is disposed at the first end of the handle. In another aspect, the light source is preferably a point light source (e.g., a flashlight). When energized or activated, the light source interacts with at least a portion of the tube of color shifting film, producing an optical effect (typically a brilliant, multi-colored effect) visible to the user and/or observer(s). Optionally, the toy light tube includes a power source electrically coupled to the light source in conjunction with a switch to control activation of the light source.
The color shifting film utilized in the present invention comprises alternating layers of at least a first and second polymeric material, wherein at least one of the first and second polymeric materials is birefringent, wherein the difference in indices of refraction of the first and second polymeric materials for visible light polarized along first and second axes in the plane of the layers is at least about 0.05, and wherein the difference in indices of refraction of the first and second polymeric materials for visible light polarized along a third axis mutually orthogonal to the first and second axes is less than about 0.05. Preferably, the color shifting film has at least one transmission band in the visible region of the spectrum and at least one reflection band (preferably having a peak reflectivity of at least about 70%, more preferably, at least 85%, even more preferably, at least 95%) in the visible region of the spectrum.
In another aspect, preferably at least one of the first or second polymeric materials of the color shifting film is positively or negatively birefringent. In another aspect, preferably the difference in indices of refraction of the first and second polymeric materials for visible light polarized along first and second axes in the plane of the layers is xcex94x and xcex94y, respectively, wherein the difference in indices of refraction of the first and second polymeric materials for visible light polarized along a third axis mutually orthogonal to the first and second axes is xcex94z, and wherein the absolute value of xcex94z is less than about one half (in some embodiments one quarter, or even one tenth) the larger of the absolute value of xcex94x and the absolute value of xcex94y.
Further with regard to the color shifting film, at least one of the first and second materials can be a strain hardening polyester (e.g., a naphthalene dicarboxylic acid polyester or a methacrylic acid polyester). In other aspect, the first polymeric material can be polyethylene naphthalate and the second polymeric material polymethylmethacrylate.
In one preferred embodiment of the present invention, the tube of color shifting film is configured to resemble an elongated cone. In another preferred embodiment, the tube of color shifting film is configured to telescopically extend and retract relative to the handle. During use of the latter, the tube of color shifting film can be rapidly displaced via movement of the handle, enhancing the visual effect.
Certain preferred color shifting films used in the present invention are advantageous over prior art color films in many respects. For example, while color shifting films based on isotropic materials are known, these preferred films exhibit decreased reflectivities at non-normal angles of incidence, which diminishes the intensity of the reflected wavelengths at non-normal angles of incidence. Hence, such films appear lighter and have less saturated colors at oblique angles. Other color shifting films change their spectral profile as a function of angle, resulting in diminished color purity and/or less dramatic color shifts with angle.